1. Field of the Invention
The present invention relates to an image processing apparatus. More particularly, the present invention relates to an image processing apparatus and method for conducting image signal processing in order to increase the sharpness of an image.
2. Description of the Related Art
For example, when executing image signal processing such as changing the resolution of an image, there exists related art that sets coefficients as follows in a filter used in digital signal processing. First, a plurality of coefficients are computed in association with each of a plurality of fixed parameter values corresponding to the different resolutions. Next, a function corresponding to a curve that approximates these discrete coefficients is computed, and combinations of coefficients for the computed function may be stored as coefficient-related data for the filter coefficients, for example. Then, when executing image signal processing, filter coefficients are computed by substituting parameter values obtained according to user input, for example, into the variables of the function given by the coefficients expressed as the stored coefficient-related data. Filter processing based on the computed filter coefficients is then conducted. (See Japanese Unexamined Patent Application Publication No. 2002-359820 (FIG. 1), for example.) In so doing, filter processing can be conducted without storing a large number of filter coefficients corresponding to each of the possible parameter values, and it becomes possible to reduce memory.